Pneumatic tools are commonly used in the construction industry. One type of pneumatic tool is a pneumatic nailer, which is a tool that is used to drive nails into a workpiece. In a standard setting, a pneumatic nailer is coupled to a source of compressed air, typically from a portable air compressor. The pneumatic nailer usually includes a magazine that holds numerous fastening members, such as nails. The nails are typically arranged in a strip or a coil, in which the nails are uniformly spaced apart from each other and are loosely connected by a clip made from a thin layer of plastic, paper, and/or a resin-type material.
To drive a nail into a workpiece with the pneumatic nailer, the operator places an ejector tip of the nailer against the workpiece. After the tip is depressed, the nailer becomes responsive to force applied to a trigger of the nailer. When the trigger is depressed, the nailer activates a pneumatic actuating mechanism inside the nailer, which plunges a ramming member from a ready position toward one of the nails of the strip of nails. The ramming member strikes the nail and causes the nail to disengage from the strip of nails, exit through the ejector tip, and drive into the workpiece. When the operator releases the trigger or the ejector tip is removed from the workpiece, the pneumatic actuating mechanism quickly returns the ramming member to the ready position, where it remains until the sequence is repeated.
Some pneumatic nailers use compressed air to both drive the ramming member toward the nail and also to return the ramming member to the ready position. Generally, it is desirable for pneumatic nailers to efficiently utilize the supply of compressed when driving and returning the ramming member. The efficient use of the compressed air results in less power cycling of the air compressor, which not only conserves electrical power and/or reduces fuel consumption (depending on the type of air compressor), but also increases the operational life of the air compressor.
Therefore, a continuing need exists for a pneumatic nailer that efficiently uses compressed air to drive nails, and that also efficiently uses compressed air to return the ramming member to the ready position.